Great instructable. A word of warning to folks though... Hard drives are EXTREMELY refelective. I did this a while back and very quickly got complaints from neighbors, and my wife about the sun reflections these cause. Put this in a shaded area or you will never be able to look outside again.

Neat, but just a word of warning - Don't try this with 2.5" laptop drives as some of the platters are made of glass. I bent one of these once to see what sort of 'metal' they were made of and it shattered into a billion high velocity razor sharp shards. Live and learn . . .